Related Party Transactions - Acquisition of Spring11 Ownership Interest from Cantor (Details) - Equity Purchase Agreement	1 Months Ended
Feb. 28, 2023 USD ($)
Related Party Transaction
Related party transaction, amounts of transaction	$ 11,530,598
Newmark S11 LP LLC
Related Party Transaction
Equity method investment ownership percentage	33.78%
Spring 11 \| Newmark S11 LP LLC
Related Party Transaction
Equity method investment ownership percentage	25.62%
Spring 11 \| Newmark S11
Related Party Transaction
Equity method investment ownership percentage	100.00%

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of transactions with related party during the financial reporting period.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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